Lucy Holmes, of Bilton, East Yorkshire, went to Hull Royal Infirmary after she injured her leg while rollerskating.
But, after a six-hour-long wait, doctors sent her home without taking any X-rays and despite her not being able to walk.
Her family said a doctor told her to keep trying to walk on it.
But Lucy was in so much pain her family took her back the next day and, after an X-ray, she was diagnosed with a spiral fracture.
Lucy said: “It was a horrible experience.”
Her father, Lee, said: “We feel really guilty because we were getting annoyed with Lucy on the Sunday night and said she must be overacting.”
He said: “There is something drastically wrong when you can’t get an X-ray. We know there have been some cuts but is my daughter not worth an X-ray?”
A spokesman for Hull and East Yorkshire Hospitals NHS Trust said it was not possible to comment on individual cases.
It is understood the trust is looking into the case.